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Wilkinson Microwave Anisotropy Probe DR4

The data made available through this page has been updated. The most recent version of this data may be accessed through https://lambda.gsfc.nasa.gov/product/wmap/current/"

DR4 Point Source Catalog

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This is a catalog of 471 point sources detected in the seven year WMAP skymaps independently from any previous surveys. The sources listed inthe catalog were detected as ≥ 5 sigma peaks in WMAP maps thathave been weighted by the square root of the number of observationsand optimally filtered for point source detection. The position ofeach source is obtained by fitting a Gaussian profile plus abaseline to each detected peak. Of the 471 detected sources, 444have one or more possible 5 GHz counterparts. Of the sources withno 5 GHz identification, some are close to the detection threshold and may be spurious. The catalog lists the following parameters foreach source:

Cols 1 -- 2Right Ascension and Declination (2000)
Cols 3 -- 4Galactic Longitude and Latitude
Cols 5 -- 9WMAP Flux (Jy)
Cols 10 -- 14Flux Error (Jy)
Cols 15 -- 165 Ghz Identification
Col 17Flag for multiple 5 GHz identifications
Col 18WMAP DR1 Identification Number
Col 19WMAP Spectral Index
Col 20WMAP Spectral Index Error

The CMB-free method identifies 417 point sources in a linear combination mapformed from Q, V, and W band maps using weights such that CMB fluctuationsare removed and flat-spectrum point sources are retained. Source fluxesare then estimated by integrating the Q, V, and W temperature maps within1.25 degrees of each source position and applying a correction for Eddingtonbias due to noise. The catalog lists the following parameters foreach source:

Cols 1 -- 2Right Ascension and Declination (2000) (deg)
Cols 3Source Id
Cols 4Optical Identification from NASA Extragalactic Database
Cols 5 -- 6WMAP Q-band Flux and error (Jy)
Cols 7 -- 8WMAP V-band Flux and error (Jy)
Cols 9 -- 10WMAP W-band Flux and error (Jy)
Cols 11 -- 125 Ghz Identification
Col 13Distance to the 5 GHz counterpart
Col 14Source note

Additional Information

  • "Extragalactic Point Source Search in Five-Year WMAP 41, 61, and 94 Ghz Maps", Chen, X., and Wright, E.L., 2009, ApJ, 694, 222

Back To WMAP DR4: Derived CMB Products

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